The third dimension in GIS: Practical issues and Future trends Presented during CSI-2011 at Ahmedabad on 02 Dec. 2011 Dr. PK Srivastava MD, GeoSpatial.

The third dimension in GIS:The third dimension in GIS:Practical issues and Future trendsPractical issues and Future trends

Presented during CSI-2011 at Presented during CSI-2011 at Ahmedabad on 02 Dec. 2011Ahmedabad on 02 Dec. 2011

Dr. PK SrivastavaDr. PK Srivastava

MD, GeoSpatial Delhi LtdMD, GeoSpatial Delhi Ltd

OverviewOverview

• Definitions

• Data sources and examples

• Visualisation of elevation

Definition of heightDefinition of height

Direction of verticalDirection of vertical

Figure 8.2

Deflection of the verticalDeflection of the vertical

Data sources and examplesData sources and examples

• Global topography

• CartoDEM

• LunarDEM

• Laser mapping

Global topographyGlobal topography

National DEM from Cartosat-1

• Study team considered three approaches :

– Approach 1,2 COTS-based, – Approach 3 Indigenous (2006)

using Augmented SST & High Density image matching (Approved)

• Refined specifications & Objective: ~10m DEM seamless homogenous with coregistered 2.5m orthoimage

– Segment-based production (ASST)

– Strip-level mosaicing– Quality Verification & Editing– Tile archival & Dissemination

Ortho-Image Hilly Terrain Near Jammu

DEM

DEM REPRESENTATION OF SONAMARG AREA IN SRINAGAR

Perspective view of Sonamarg

DEM generated for Himalayan region using new image matching algorithm

LEGEND    SSTS run using GCPS collected from neighboring segment     Not processed    Outside India   Completed

Note : SSTS in the southern  generated  using GCPL library (pink  color  in this region  represents non availability of cloud free data )

LunarDEM and Lunar Mapping

Part of Mare OrientaleOrthoimage Color Coded DEM Contour Image

Strip width: 20 km Strip length: 65 km

Ortho-Image, DEM and Color Coded DEMOrbit Number: 798; DOP: 13 Jan. 2009

-8000 Km 8000 Km

Ortho DEM Color CodedDEM

Detailed View

0 3 Km

Height Range: - 4386 to + 4120 m

LiDAR

• LiDAR is technology that uses lasers to measure objects

• Each beam hitting the ground returns the X, Y and Z (elevation) coordinate at that location

• Accuracy of each position is accurate within centimeters

Aerial coverage

LiDAR coverage

Visualisation of ElevationVisualisation of Elevation

• Cartographic presentations

• Contours

• Built up area models in GIS

Colorcoded Raster DEMColorcoded Raster DEM

Hillshade

Elevation raster with hillshade

Slope

• Slope identifies the steepest downhill slope for a location on a surface

• Higher the slope value, the steeper the terrain

• Slope can be expressed as degrees or percent

• Formula: Percent Slope = (Rise/Run) * 100

• Slope approaches ∞ as the angle reaches 90°

An example: 100’

(100/100) * 100 = 100% Slope

45°

100’

Percent slope

Percent slope with hillshade

Slope Variations in color result from

hillshade

Percent slope with hillshade

Percent slope viewed in 3-dimensions

Percent slope with hillshade

Aspect Defined

• Aspect is the direction that a slope or hill faces

• Potentially significant as a restoration tool to identify species appropriate for certain faces

Aspect

Percent slope viewed in 3-dimensions

Percent slope with hillshade

Aspect

Percent slope viewed in 3-dimensions

Percent slope with hillshade

Contours

Digital Elevation Models

888.40 890.32 891.78 891.38 892.78 893.81

887.50 889.10 890.36 890.21 893.47 892.57

884.75 887.85 888.45 887.78 890.40 892.59

885.35 886.12 884.35 886.52 891.54 894.75

888.37 887.30 886.67 888.55 898.40 895.54

5’

898.40 884.52 884.32 889.54 896.35 895.35

0’ 0’ 5’

Digital Elevation Models

893.81 891.78 892.78 890.32 891.38 888.4 888.40 890.32 891.78 891.38 892.78 893.81 893.47

892.57 890.36 890.21 889.1 887.5 887.50 889.10 890.36 890.21 893.47 892.57 892.59

894.75 890.898. 888.45 887.85 900 4 887.78 884.75 887.85 888.45 887.78 890.40 892.59 895.54 884.75

891.54 896.35 886.12 895

885.35 886.12 884.35 886.52 891.54 894.75 886.52 885.38 895.35 88.3 A 888.55 884.35 887.3

886.67 7 890 888.37 887.30 886.67 888.55 898.40 895.54 889.54

B 888.4

898.40 884.52 884.32 889.54 896.35 884.52 885

895.35 884.32 C

D Elevation grid 880

E 875

F 2

3 4 5 6 Extrusion of grid values

Digital Elevation Models

888.40 890.32 891.78 891.38 892.78 893.81

887.50 889.10 890.36 890.21 893.47 892.57 900

884.75 887.85 888.45 887.78 890.40 892.59 895

885.35 886.12 884.35 886.52 891.54 894.75

A 890 888.37 887.30 886.67 888.55 898.40 895.54

B 885

898.40 884.52 884.32 889.54 896.35 895.35 C

880 Elevation grid D

E 875

2 3 F 5 6

Continuous elevation surface

White modelWhite model

Generic modelGeneric model

Textured modelTextured model

• Gopaldas.avi

Shortcut to Gopaldas.avi.lnk

Thank YouThank You

Author can be contacted at [email protected]

1,000,000 Graticule extent (LCC/TM) with 1 :250k Grids

1:1000,000

1:250,000

Polar Stereographic Projection for latitudes between 70 and90

Typical Chandrayaan-1 Topo Ortho-image Map

Part of PLASKETT Crater Viewed by Chandrayaan-1 TMC from 200 kmOrbit No.:2714; DOP: 22-06-2009; Ascending

FORE NADIRAFT Detailed View

0 4 Km

Mandate - To Design, Develop, Procure and Integrate Hardware and Software for a complete INSAT Data

Processing facility at IMD, Delhi

KALPANA-1 & INSAT- 3A ( VHRR & CCD)• Installed and operational at BES & IMD on 24 x 7

(SAT Completed)• Data Acquisition and Quick Look Display• Data Products Generation• Geophysical Parameters (AMV,OLR,UTH,QPE,CMV/WVWV, SST, AOD, NDVI)

INSAT Meteorological Data Processing System(IMDPS) INSAT Meteorological Data Processing System(IMDPS)

IMDPS Activity ScheduleIMDPS Activity Schedule

• INSAT 3D Design Review for DAQLS and DP elements : Jan 2007 • ATBD for 21 Geo-physical parameters completed : Mar 2007• Discussion on GPR (with IMD) is completed : Dec 2008• All Procurements of Target Hardware including SIDS : Completed

Hardware Shipment to IMD (DAQLS, DPPR) : Completed DAQLS (K1,3A) : Completed UPS Installation at IMD : Completed Networking at IMD : Completed System Procurement & Installation at IMD :

Completed• Infrastructure Readiness at IMD : Ready • Algorithm Theoretical Basis Definition (ATBD) : Completed• Design Review & Prototype development : Completed• INSAT 3D Software Development : In final stages• Factory Acceptance (FAT) at SAC : Completed• System Integration and SAT (K1,3A) : Completed • Software & Hardware Training : completed • Operationalization at IMD (24 x 7) : Completed (K1 & 3A) • SAT at IMD with INSAT-3D : Launch + 6 Months • GP Products Validation : 3A/K1 : In Progress

Switch to Demo of Terrain visualisation

This software is developed in-house by carrying out low level programming of graphics card as a visualisation and

analysis tool